Jacques B. wrote:
That is a lot of cpu use and I think those suggesting the use of the
Rescue disk I have this:
The Rescue disk does not have dd. It also lacks RAM and will NOT work. I
was getting email and doing things with my computer while dd was sending
it to the other Hard Drive.
It worked just fine.
Karl F. Larsen, AKA K5DI
What lacks RAM? I'm assuming you mean your computer. Anyhow, not
important at this point. On to more important issues.
More accurately you should say "So far it is working just fine".
Imagine photocopying a book. You photocopy the front of the book, the
foreword, the table of content with the list of chapters and headings,
then start photocopying the chapters. While you are doing this you
continue to make changes to the book. You are now at page 20 of 100
photocopying away. All at the same time you change the chapter name
of the chapter on page 45 (now that doesn't match what you photocopied
in the beginning). You remove a paragraph on page 15 (but you already
photocopied it so it's already in your copy). You delete page 19 so
now your book is from page 1-99 but you already copied that page so
it's on the copy. You update your alphabetical index at the end of
the book when you are up to page 50. So the index tells you that
something is on page 20 but it's really page 21 in your copy because
you deleted page 19 after photocopying that page so your updated copy
has it on page 20 but it is on page 21 on the original revision. And
it goes on.
Now dd is doing the exact same thing. It's copying stuff over
complete with pointers to where to find certain data and pointers to
free space on the drive. That is written at the beginning of the
copying process because it resides there. Yet you are still using the
system so what was marked as unallocated space is in use by the time
dd gets to it. And what was marked as used disk space when dd copied
over the index is now unallocated space because you deleted something.
It can make a real mess of things. Problems may manifest themselves
pretty quickly, later on, or apparently not at all if you are lucky
(but that will not mean that stuff isn't misaligned with the index
because it's impossible for that NOT to happen given your scenario).
The choice is yours. Run with it and keep your fingers crossed or
exercise an once of prevention now to avoid a potential pound of
headaches later on and redo the process using a live CD as previously
explained. Or pursue someone else's advice on how to ghost a drive
onto another one (entirely different approach than dd and certainly
more efficient if this is something you will be repeating somewhat
regularly - but again you would not do that on a live system...).
Jacques B.
OK. I changed my little paper so 6. says this:
6. Always run dd in the source computer. If your worried about computer
activity during the transfer get out of X windows by using Cont-Alt-F1
and then run dd.
--
Karl F. Larsen, AKA K5DI
Linux User
#450462 http://counter.li.org.
